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4/22/2019 5:32:20 PM
Posted: 8/19/2006 5:35:49 AM EDT
DETERMINING ROUND COUNTS, THERE IS A BETTER WAY.

Checking wear on parts as previously indicated is good to tell if a gun is still new and no problem with that but there are other things that wash out ARs.

One is hammer and trigger pin holes elongating. Last I heard 40% of AR receivers are scrapped at first depot rebuild.

There is a <> shaped gage plug used to check these holes, if it goes in they scrap the receiver. Elongated holes can and will affect trigger pull and sear engagement.

Next is erosion gage. First is the military gage with one ring on it. It measures how far the erosion has progressed down bore. It is slid in from the back of receiver and if the ring is visible it generally means the barrel is still capable of meeting military dispersion (a term we call accuracy) requirements.

First you have to remember the M16A2 ACCEPTANCE dispersion for 10 shots at 100 yards with select ammo was 4.5" and REJECTION is 7.2" at 100 yards. Now to me as a competition shooter anything over an inch is a plinking gun or home defense gun so the military gages are nice for the collect but relatively useless in determining round counts.

There is a far superior gage I have used. The full story can be read at:

http://www.beastwerks.com/throat_erosion/throat_erosion.htm

Click on that and you will see a AR gage designed for all AR barrels (chrome moly, chrome lined, military, commercial, and stainless) and a nice explanation of how they are used. I have several of these gages for different calibers and they are very nicely done and you can track exactly where you are in the round life of your barrel.

They are calibrated off new barrels so you have a rough idea of how many rounds are on a particular barrel. All we need now is feed back from guys who keep round records as compared to group size with handloads to tell us how many rings on one of these gages equals what size groups with good handloads.

Had a nice discussion with young man who won Civilian Service Rifle Championship about three years ago. He says he gets about 2000 rounds on his tube and it is gone.

Now you have to remember for a match shooter when the rifle opens up to over an inch it immediately becomes a Tomato Stake or REBAR for that next concrete pour.

Also MILSPEC ammo really sucks in terms of dispersion. Most ARs with M193 acceptance ammo target about 3" at 100. As they say in computer lingo, GARBAGE IN GARBAGE OUT.

Now military contract has extremely liberal acceptance standards. I noticed a couple vendors are saying MOA as standard for varmint rifles. This is with commercial bullets and or handload ammo which is far superior to most MILSPEC ammo. There is one exception.

Genuine FN SS109 shoots extremely well for MILSPEC ammo. I have had it shoot ten shots in an inch or slightly over on several guns but genuine FN SS109 is hard to find. If you can ever get genuine SS109 by FN jump on it and lay it in as it is rare.
It is BERDAN primed but if you ain't reloading anyhow????

So round counts at low rounds are really insignificant unless someone is passing off new rifle.

The M16A2 when tested by Marine Corp went 12,000 rounds per rifle and at 12,000 the average was 7.2" at 100 yds. using genuine FN SS109 ammo.

I was told by a Test Director at Aberdeen that M193 on M16A1 shooting a cold schedule would go 22,000 rounds.

I was told by Marine Major who had 50 new M16A1s issued to him and he used them to FAMFIRE new personnel that he kept a round count on each rifle. Every time they went to range they fired 30 rounds and returned to armory where they were cleaned with commercial cleaning rods, not military cleaning rods. In short they were well cared for and at no time was cleaning rod inserted from muzzle. (best way to ruin barrel)

He told me when he left that facility he had 50,000+ rounds on each weapon and they were still very accurate insofar as military accuracy was concerned.



Link Posted: 8/19/2006 6:14:08 AM EDT
Thanks for the very informative post! And welcome to arfcom - hope we hear more from you. One question- I don't understand the military dispersion limits - if 4.5 in. is "acceptance", and 7.2in. is "rejection", then what about in-between? Acceptable or unacceptable?
Link Posted: 8/19/2006 6:23:29 AM EDT
Great writeup... I always wondered whether our armory conducted round counts.
Link Posted: 8/19/2006 7:15:13 AM EDT
[Last Edit: 8/19/2006 7:18:46 AM EDT by Humpy70]
AS NEW ANYTHING LESS THAN 4.5" is acceptable. Once it goes in the SYSTEM all there is use is the military reject gage and most folks I think don't understand the concept or bore erosion. The article on the erosion gage I referenced gives a very good discussion on throat erosion.

I suspect if you had a rifle delivered that printed 4.4" your barrel life would not be as long since most come in at 3 to 3.5".

The military normally does not do the round count number. That would make sense so obviously not done ! ! ! The guy that did the round counts was a former member of the Marine Corps Rifle Team thus he had a higher than usual interest in accuracy, round life etc. It was amazing in the times I talked to him, we agreed on everything right down the line. Then again he was a competition shooter as am I and our experiences were very similar except he got free BBs to shoot.

The absolute critical thing is CLEANING. Most folks recognize the AR is like women, neither likes to be dirty and both will complain when they are haha.

For you guys that sell barrels for a living you are not going to want to see the next few paragraphs.

I have been doing experiments for last two years on brand new 0 rounds rifles based on what I have observed with known round history on other rifles with bore scope.
Well a little background. New barrels will normally have the reamer marks burned out of the throat in 100 to 150 rounds.

I have had friend bring me Rem 700 Police Sniper rifle with barrel shot out at 600 rounds. It was set back and new chamber cut with short throat/tight neck and this time it went 1100 rounds. When the barrel was sectioned with bandsaw the rifling was gone about 1/2" downbore. I know a gunsmith in Indiana who has seen three such Rems with barrel gone around 600 rounds.

I took a new 700 Remington in 308 (a sporter barrel no less) and a new Model 70 Win in 30.06 and I had a theory so I borescoped and took Erosion Gage Readings at 0 rounds. Then I started shooting except I changed cleaning schedules. Instead of cleaning at end of the day I cleaned just as soon as a string was finished and barrel was warm. I used Ed's Red Homebrew bore formula. (found on any search engine under ED's RED). I would clean every 12 rounds to 22 rounds just as soon as I could get bolt out and a wet patch downbore. I borescoped and did erosion gage readings every 50 rounds.

OK as I said reamer marks disappeared at 100 to 150 rounds on other guns. And barrel went at 600 rounds on a Rem 308. My Rem barrel now has 730 Rounds AND STILL HAS REAMER MARKS IN THROAT ! ! ! ! ! Erosion gage has not moved in last 400 rounds! ! ! ! THe Mod 70 30.06 has 550 rounds and still has reamer marks.

Then it hit me. When propellant is burned it leaves what we refer to as powder residue. A chemistry type would call this carbon. It is long known in the metallurgy field you add carbon to steel to make it hard/tough etc. I talked to a chemistry PHD and told him my theory that carbon when first formed is soft and when cools it becomes hard. He agreed but didn't know the time factor for this to occur.

So my theory is if the carbon is allowed to cool it will act like cement and set up. OK now you have a dirty barrel that has cooled down with carbon getting hard and you fire more rounds. Carbon being far harder than steel would therefore become abrasive in nature and now you have this copper jacket trying to grind the carbon in the barrel at high pressure. Result you have erosion.

To prove this theory I have run two tests with the 308. I shot one continiuous 30 shot string at 60 second intervals and barrel temp was measured with laboratory mercury thermometer inserted 3" in muzzle. I had a barrel temp of 160F at muzzle. I cleaned and bore scoped, no movement of erosion gage and no change in reamer marks in throat.

Later I reconducted the test and shot 30 rounds at 30 second intervals and barrel temp got to 190F. Still no erosion gage movement no notable reamer mark removal.

I once saw a test barrel with unknown number of rounds on it in 308. Rifling was completely gone for three inches downbore and it still shot 1.5" at 300 yards. No one had bothered to keep a round count on it. I could have screamed when they told me no round counts were kept.

The bottom line is it was fired 15/20 rounds and cleaned immediately after firing and put away. Never fired with dirty barrel and barrel never cooled off.

I once read an article where Roy Dunlap said a factory barrel could be taken to 10,000 or more if cleaned properly. He did not define properly but based on above I now completely agree with that statement.

I have a 30.06 with 4200 rounds on tube. Set back at 2500 rounds. It still shoots about 5/8". It has not been cleaned properly until about a hundred rounds ago and from now on it will have TLC and we will see how long it goes.

I was told by a 6th Army gunsmith they took a chome lined barrel off a M14 with 22,600 rounds on it and it was still shooting acceptance. Acceptance was 4.5 inches at 300 yards on a match rifle for them. He was afraid it was getting ready to go out at a match and pulled it.

Another armorer told me they pulled a rattle battle barrel that was still shooting 100% hits at 600 yards and the rifling was gone all the way to the gas port ! ! ! ! ! !

Rattle Battle barrels start , go damn hot (20-22 rounds in 50 seconds) and dont cool till end of string and are cleaned.

Name of the name guys is treat your rifle bore well and it will be happy. Or in the South "If mama ain't happy, ain't nobody happy."

Link Posted: 8/19/2006 7:22:51 AM EDT
[Last Edit: 8/19/2006 7:24:23 AM EDT by AtlantaFireman]
Will putting Kroil, Ed's Red, Mobile One, or something like that down the bore during shooting help keep erosion down? I'm not talking about cleaning the bore with a rod/patch, just run the stuff down the bore while hot and set on end to let it drain out.
Link Posted: 8/19/2006 8:03:22 AM EDT
I wouldn't just pour it down bore and leave it, very good way to split a barrel. I have soaked barrels with a copper removing solution but always wipe it out before firing.

BARREL MUST BE WIPED DRY BEFORE FIRING IF YOU DO SUCH. I WOULD NOT DO IT!!!


Oh yeah one more thing. When barrels fail for some unexplained reason theY split at 3:00 and 9:00 orientation. If this happens and your hand is round forearm you will most likely lose thumb and fingers being sheared. Rarely does a barrel split at 12/6 oclock. Should that happen you may well keep your thumb but lose half your hand.
THIS IS NOT A ESTIMATE, A GUY NAMED MARQUART HAD FINGERS OF LEFT HAND SHEARED WHEN BARREL FAILED.

On conventional cleaning methods (cleaner on patch and run in with rod) and dried afterwards.

I have tried a number of different things in cleaning. Kroil should work but far more expensive than Ed's Red. You can make three gallons of ED's Red for about 14.00 including the cost of a 5 gal Blitz can from Wally World.

For instance the other day I was visited by a sergeant in the 82nd ABN. He said he was having wild shots they could not account for when they started shooting and towards end of string it started shooting nice small groups.

I asked him what he was using to clean with and he said Break Free. I took him out back to my range and let him do the shooting. He medaled at Camp Perry in Long Range Championship last year he went to Camp Perry before going active.

I let him shoot 5 rounds with 308 using FED MATCH,to rezero at 100 yards. I then let him watch me clean barrel with Eds Red and he shot a 3/4" group. Then I cleaned with GI Rifle Bore Cleaner dtd l972 and he shot a 3/4" group.

Then I hunted around and found some Break Free I have had for several years and cleaned it in the exact same manner and his group went to 2.5". That reflected what I have had happen on several occasions and know of several other folks experiencing same thing, wild shots after cleaning.

Cleaning was as follows: Bolt removed and rod guide inserted. Wet patch down bore for ten up and back cycles. Patch changed and repeated another ten cycles. Then a third patch ten cycles. Then a dry patch three passes.



Link Posted: 8/19/2006 8:16:52 PM EDT

Originally Posted By Humpy70:
I let him shoot 5 rounds with 308 using FED MATCH,to rezero at 100 yards. I then let him watch me clean barrel with Eds Red and he shot a 3/4" group. Then I cleaned with GI Rifle Bore Cleaner dtd l972 and he shot a 3/4" group.

Then I hunted around and found some Break Free I have had for several years and cleaned it in the exact same manner and his group went to 2.5". That reflected what I have had happen on several occasions and know of several other folks experiencing same thing, wild shots after cleaning.
So after shooting 3/4" groups, just cleaning the barrel with BF and everything else the same, trippled his group sizes?
Link Posted: 8/19/2006 9:09:59 PM EDT

Originally Posted By dmk0210:

Originally Posted By Humpy70:
I let him shoot 5 rounds with 308 using FED MATCH,to rezero at 100 yards. I then let him watch me clean barrel with Eds Red and he shot a 3/4" group. Then I cleaned with GI Rifle Bore Cleaner dtd l972 and he shot a 3/4" group.

Then I hunted around and found some Break Free I have had for several years and cleaned it in the exact same manner and his group went to 2.5". That reflected what I have had happen on several occasions and know of several other folks experiencing same thing, wild shots after cleaning.
So after shooting 3/4" groups, just cleaning the barrel with BF and everything else the same, trippled his group sizes?


I can't speak for trippling, but I noticed when I used to clean with breakfree that it would take the first 5-10 rounds before the rifle settled into a group, and sometimes the first and second rounds would be kicked way out to the 7 or 8 ring. This was after using breakfree to clean the bore and dry patching until all residue appeared to be gone.

I switched to a 50/50 mix of kroil and shooters choice and moly, no wild shots. The theory at the time was teflon residue from the breakfree.
Link Posted: 8/19/2006 9:20:15 PM EDT
[Last Edit: 8/19/2006 9:21:05 PM EDT by Dano523]
Link Posted: 8/19/2006 9:20:43 PM EDT
Yes indeed. Test Technician at Quantico for Marine Rifle Team told me they put it in M14 Match rifles on their machine rest and it shot all over the place. Took 15 to 18 rounds to get them back to where they would group.

I have yet to see a competition highpower shooter run it in their match barrels.

Give it a try and shake it up real good to get the teflon flowing and see what happens.
Link Posted: 8/19/2006 9:22:12 PM EDT
so to slow erosion, is it better to clean when warm? or just not firing a cold fouled barrel.
Link Posted: 8/19/2006 9:28:10 PM EDT
I find it is much easier to clean when it is warm.

More proof. Unscrew the expander out of your FL die. Look at it with a magnifying glass. Believe you will see it is scored all to hell with corresponding marks inside necks.

Now think about this, how does brass score hardened steel expander???????? Yet the outside of the case does not score the size die?

Now look in case neck before you size and and see what you see inside case neck. Carbon. This is why you want to clean them out with brush.

The expander button is much harder than your rifle barrel and it is getting scored.
Link Posted: 8/20/2006 1:46:18 AM EDT
Just to touch on brass cleaning:
When I tumble brass, I use corn cob media with Midway brass cleaner added (does not contain an abrassive or ammonia: citrus based...well, smells like it anyway). I also add about 1-2 tablespoons of mineral spirits; I use a standard Midway tumbler. I have noted that the mineral spirits remove powder scoring (carbon?) extremely well.

I have also used walnut hulls ("Lizard Litter", sold at Petsmart, Wal-mart, etc: inexpensive, relatively) for tumbling. However, walnut hulls do not leave a bright luster like corn cob media, but it cleans much faster.
Link Posted: 8/20/2006 5:33:29 AM EDT
YOU ARE RIGHT ON TARGET, CARBON IS THE ENEMY FOR EXPANDER BUTTON WEAR ETC.

ONCE YOU REMOVE THE CARBON THE CASE WILL COME BACK OUT OF THE DIE OVER THE BUTTON MUCH EASIER.
Link Posted: 8/20/2006 7:59:46 AM EDT
I have a friend that used to work at Aberdeen proving grounds years ago. Here's what he related to me when they tested a new product called Breakfree. Back when it first came out. They shot 105's horizontal at a 1000 yards for 5 shot groups on a piece of notebook paper. Cleaned beforehand with the standard military bore cleaner. They had a nice group in the center of the paper with several shots touching. After cleaning the tube with Breakfree. They couldn't hit that piece of paper with 5 shots using the same sight setting. It made the 105's wild until they burned the Breakfree out of the tube. I think that test was conclusive enough to ban the use of Breakfree in artillery and military regs soon followed stating such.
Link Posted: 8/20/2006 11:21:28 AM EDT
[Last Edit: 8/20/2006 11:21:54 AM EDT by warren-hpf]
I'm getting one of those gauges. I think it would be much easier to use than a stoney point gauge, and provide more a acurate results.

Here's a link to some thoughts on barrel changing by Konrad Powers: www.illinoishighpower.org/konrad/miscellaneous_technical_information.htm
Link Posted: 8/21/2006 3:05:24 PM EDT
UPDATE ON ED'S RED (MAKE IT YOURSELF BORE CLEANER)

We have a very sharp PHD Chemical Engineer that goes to our church and I asked if he could figure out the freeze point of Mercon Dexron, K1 Kerosene and Mineral Spirits.

I got a email from him and he is estimating -60C or -76F which will take care of most areas I will be shooting in.

The only other thing I know that even approaches this is military arctic lubricant called LAW.

Based on this I believe I will be making my own bore cleaner from now on.
Link Posted: 8/21/2006 3:24:56 PM EDT
great info, Humpy........thanks for sharing.

Have you read about the new SOPMOD recommendations for a digital 'shot count' device?

Supposed to be able to provide armorers an instant measure of round count to prevent problems associated with weapons 'past the point of scheduled part replacement'
(barrels, bolts, etc.)

Facinating stuff.

LINK Page 40 to 52. Info originally posted by SgtSauer SOPMOD and the M4

SgtSauer's SOPMOD thread
Link Posted: 8/21/2006 5:47:12 PM EDT
Yes I remember it. At least I think it is same thing. Started life as a counter on a carpenter's air drive nailer to keep the carpenters from stealing the nails and to see how many nails they were driving a day???

I had forgotton about that thing but didn't really see the reality for small arms in it as they have a limited round life insofar as gov't goes and weapons are disposable. For instance the 9MM pistol was supposed to have a 10,000 round life but none got there so they dropped requirement to 5000 rounds.

I really didn't see the advantage of going to the expense of putting something on a system that was low dollar anyway.

Next you got a problem of the kids completely submerging their ARs in Break Free. I saw it 25 years ago and heard it is still happening as of three weeks ago.

I kind of classified that as in the same catagory as a safety on a revolver.

Considering the fact that John Unertl told me he got sniper scopes in for repairs from Marines who rammed cleaning rods throught he rear of their scopes....................

I had rather see the gov't spend money on something more beneficial to the troops like the new sight systems. Now that I can go with but a odometer for a rifle?????
Link Posted: 8/22/2006 3:10:55 AM EDT
http://www.geocities.com/binarybytes/308erosion.JPG

OK here we have a section of barrel that shows the effects of carbon scoring. Note in the throat just ahead of the chamber the scoring lines are straight while the rifling is at very slight angle. Obviously a copper jacketed bullet won't cause this kind of damage to a barrel. At the very start you see gas erosion in at the intersection of chamber/throat.

Note also the rifling is worn down even with grooves. This is why the erosion gage is allowed to go further into the barrel as round life increases as the gage only touches the tops of the lands.

Just guessing I am estimating this at about 6 rings of forward movement. I did not have a gage when this barrel was sectioned and the friend that owned it did not keep round records. I would hazard a guess he has 6000 to 7000 rounds on it.

On bolt guns with enough stock on barrel to cut off threads and set them back prior to the enhanced cleaning schedule I am now doing, I was setting barrels back in 30 cal about 2500 to 3000 rounds and getting 2 to 3 rings of movement on the erosion gage.

With the enhanced cleaning schedule I am hoping to get maybe 4000 to 5000 before set back. The erosion gage will tell me what is happening.

Another good thing about the gage. Like the above referenced http says, you can tell if your bullet propellant combination is causing excessive movement. Record keeping is what it is all about.

The erosion gage is the best thing a shooter can get. Next best is a borescope. I was quite lucky there and stumbled onto a mislable on ebay and fell into a 2750.00 Olympus Series 5 30 deg borescope for 200.00. You can see exactly what the erosion gage sees and you can correlate gage movement with what you are seeing.

I wish I had found the erosion gages 30 years ago and I could have probably saved a bit of money and had alot more piece of mind. If you are not gaging you don't know where you are in relation to what your barrel is being exposed to. I am sure guys have pulled barrels that were still good on ARs. It is more critical on ARs to know where you are than bolt guns because you can't set them back.

For instance a guy gave me a Model 70 30.06 sporter barrel he said was no good. Just looking at it, it was dark so I figured what the heck, I wanted to see how much wear it had and milled out a section so I could show folks what happens in front of the chamber.

I looked at it with glass and determined I had just ruined a good barrel. I am sure it would have shot if it had a good cleaning as the throat wear was nothing. Looking at it again yesterday I noted there was no scoring on the throat at all. The previous owner had shot nothing but factory ammo so had no carbon build up in case neck to transfer to the throat and it does have evidence of I would say 2500 rounds. So it wasn't a complete loss, just reinforced my theory of carbon wear.

A old saying is a man is no better than his tools comes to mind. No erosion gage and no bore scope years ago caused alot of waste and needless concern. The gage comfirmed suspicions and the bore scope reinforced it.
Link Posted: 8/22/2006 3:24:44 AM EDT
The thing that I find interesting is the some barrels still shoot very well with inches of throat erosion, while other barrels don't. I'd like to find the key to that.
Link Posted: 8/22/2006 4:16:59 AM EDT
[Last Edit: 8/23/2006 4:25:58 PM EDT by Humpy70]
I don't have the data to prove it yet but I THINK it has something to do with what happens to bullet as it leaves the case. The smoother the transition of the bullet from case to the rifling WITHOUT HAVING ITS JACKET DEFORMED appears to be the key.

I have seen barrels with rifling gone but bore looks like glass in the throat. They shot exceptionally well for many rounds and the secret was they were cleaned warm and cleaned often is the only dot connections I can make.

I am told on the 6.5MM rifles now that all are throated for the 142 Gr. Sierra bullets yet they make 107 gr bullets and being much shorter they take about a half inch of jump before they take the rifling and shoot exceptionally well even with jump. That seemingly connects that jump is not necessarily detrimental if surface of barrel is good.

That is the only theory I can come up with. Wish I had the money to buy the barrels and ammo to find out. I figure 50K would cover materials. I will donate labor haha.

Maybe one of the readers will hit the lottery and write and ask me what I need. haha.
Link Posted: 8/22/2006 5:25:16 AM EDT
Here is something else to think about: acceleration and the G's imposed on the bullet.

In an AR, a bullet goes from 0 FPS to 2800 FPS in milliseconds; I guess that's pretty much the same for any rifle. QuickShot can calculate time in the barrel. I really need an engineer or physics person to do the G's calculations again, since I forgot exactly. Basically, its something like change in velocity over change in time, with all units being the same.

If my broke-down, tired, fat memory can remember, this acceleration is something like 97,000 G's, which equates to the bullet being put under 700+ pounds during firing.

I'm thinking that, with all that change, a bullet's base/side would deform to fit the bore along its entire path down the bore: expand at start and then swag itself to the bore and rifling. This would make sense with barrels that shot well with inches on no rifling, or, in the case of Wetherby barrels, free bore.

Your statement of the bullet staying true upon leaving the case makes sense: if the bullet's nose is concentric (after leaving the case), the bullet will fly straight; if the bullet is off center, accuracy suffers. This is also backup with the the practice of High Masters of loading ammo WITHOUT a crimp on the bullets. Benchrest types go to great pains to get the neck tension the same with every shot.

The long and short of it (accuracy), I believe, is consistancy, consistancy, consistancy. If the bullet exists the same way (everything else being equal), with every shot, the bullet should go into the same hole. Of course, this is Utopia*.

*Utopia from Greek 'ou' not, no + 'topos' place. In other words, it will never happen.
Link Posted: 8/22/2006 2:43:48 PM EDT
I agree completely on consistancy is the key. Also I believe a rough throat will take copper off jacket changing the center of gravity before it leaves the barrel. Then in flight the spinning projectile not having it's core dead center will start to walk like a unbalanced spinning top. The scoring in the above photograph is sure to cause havoc on a copper jacket.

The bench rest boys study this stuff and one told me they very first sign they feel roughness in the throat they start to polish it right then. I have forgotton that little tidbit about their not liking rough throats on a low round barrel.

They take Flitz to the throat for one thing used which is one the guys passed on to me.

Do you use a erosion gage on your barrels? If so how much movement do you see in say 500 rounds?
Link Posted: 8/22/2006 5:01:24 PM EDT
I am real embarrassed to admit this: I don't keep track of throat erosion per round count. I'll look at it every now and then. For me, if a barrel shoots MOA or less, I'm happy. I go along with the Swiss and Finn philosophy of shooting: leave copper/jacket in the bore, clean out carbon, and grease the bore. All my Swiss K-31s, including my first year of production (1933), has a pristine bore, best I can tell: I don't have a borescope. All my Finn M-39s are pristine, including the ones that didn't go through depot rebuild at the end of WWII: still have WWII stock. Of course, these are not match rifles, let alone benchrest. Below are representative groups I've shot with each type rifle. To the best of my knowledge, the Swiss and Finns never used corrosive primers; we did. And I think that is where the U.S. military and we Americans go nuts: cleaning. Historically, up to the early 1950's, we used corrosvie primers and, therefore, had to immediately clean the bore, otherwise it would rust to hell and back, sometimes in a matter of hours. I think that is the reason we are obsessed with throat erosion to the extent we are.



Another 200 yard target
First time fired: 200 yards, 168 grain Sierra HPBT Match, Midway moly, 44.0 grains IMR-4895, CCI BR-2 primers, Ruag virgin brass. No alterations to firearm.



My 1955 K-31:shot at 200 yards using a Burris 4x scope, 2 1/8 inch group, June 20, 2002.
Specifics: Sierra 168 HPBT bullet using Midway moly; CCI-BR2 primers; IMR-4895 @ 45.0 grains (a bit hot); OAL 1/4 to 1/8 turn from engaging the lands using Hornady seating die; bedded with Devcon Plastic Steel; barrel completely floated; hand guard channeled; VLD chamfer; virgin RUAG brass; neck sized with Hornady die; bore conditioned with Midway Moly Bore Prep after a thorough cleaning using Rem Clean and Butch's Bore Shine. The only things left to do are cryo treat the barrel and receiver, and recrown the barrel. The trigger breaks clean at 4.25 pounds; I could hone it to 2+/- pounds. Not bad for an $80 rifle.



Comparison of GP11 bullet to a Sierra 175 grain HPBT Match (#2275) bullet



And now for the Finn M-39s



http://www.beastwerks.com/firearms/Finnish/M39/M39_images/303818/305818_09oct02_200yds_confirm.jpg



Link Posted: 8/23/2006 4:57:34 AM EDT
[Last Edit: 8/23/2006 4:28:47 PM EDT by Humpy70]
No doubt about it, the Swiss K31 and the Finnish rifles are excellent pieces. What I really like is the G11 bullet design with the long boat tail. Wish we could buy them outright for reloading in 308/30.06.
Link Posted: 8/23/2006 5:18:45 AM EDT
Humpy, Would you comment on the use of mild abrasives (eg. USP Bore Paste). I was told that the bench rest boys use this with Kroil. I've been using it in high-ROF (blasting) M16 barrels when I notice roughness in the throat despite patches coming clean. Seems to make throat smoother, but I wonder if I'm just accelerating wear?

TIA

Sam
Link Posted: 8/23/2006 8:00:13 AM EDT
Yes I slam forgot that one. I use it as well. Very good material for removing copper and fouling without harming your barrel. I apologize for leaving them out. I had my mind geared to the more general run of the mill cleaning.
(cheap) way to clean haha.
I also have some green rouge from them I forgot about. Glad you brought that up.
Don't know anyone who does not like Bore Paste. Actually

I have also come to the conclusion like Atlanta Fireman did, many barrels shoot better with copper fouling than removing it. You just have to do some testing to see what its likes and dislikes are.

I remember one of the top long range shooters in the country, L.F. Moore and I never saw him defoul a match barrel. In fact he said to me rather slyly once that he thought the copper filled the low spots. You would have to have know Larry to appreciate his humor. I have come to the conclusion that he might have been trying to give me a hint of something beneficial. Least ways for the last several hundred rounds on several rifles I have no defouled and accuracy is excellent.

I guess it is like drinking and driving. A little may be OK but a bunch is not haha. Give it a try and let us know what you find out with your own testing.

Link Posted: 8/23/2006 8:00:04 PM EDT
So do other cleaner/lubes like slip2000 present accuracy problems similar in nature to CLP?
Link Posted: 8/24/2006 3:23:31 AM EDT
Sorry, cannot comment on SLIP 2000. Have never even seen a bottle of it. Not even sure I have ever heard of it. I had a long conversation with a guy on phone last night who read my experiences with Break Free and he said he has read several such similar experiences in years past wherein others reported the nearly the same thing I did. I guess that puts me at the end of the line and in reporting my observations?

Best way to find out, after shooting say 30 rounds. Shoot three ten shot groups and remove that target and replace with another. Clean the bore with it and reapply and shoot 3 ten shot groups on the new target. If you get wild shots at first and the more you shoot the better they get you will have your answer.

Highpower target shooters only have two sighter shots at any given range and they need X ring accuracy by third shot better yet by second shot. If it looks bad at 100 think of what it will look like at 600.

I have seen weapons systems and or things I thought were great turn to crap when testing. I have also seen things I thought were crap turn out great. Until you do a thorough impartial evaluation you don't know.

I have not experienced any problem with Hoppes No 9, GI Bore Cleaner, Ed's Red, Kroil and several more I can't recall for the liquid ones. The most benefit I have had from any of them I guess is Ed's Red and you make it yourself. I have yet to find anyone that had a problem with ER. Since you make it yourself there is nothing to be gained by anyone endorsing it.

Kind of off topic I just recalled another negative experience with Break Free. In my previous shop I installed an attic vent fan.The kind you cut a hole in roof and apply. Was out working in shop one day and fan started making a noise so I killed power and disassembled it and bearings were dry.
I figured what the heck, can't hurt so lubed bearings with Break Free and it ran for a month and I was in shop and the fan was running and all of a sudden it siezed. I killed power again and took it down. This time I put Mobil 1 10W30 synthetic in bearings mixed with a little Molycote 532 powder and a year later when I moved the fan was running fine and quiet and never had a another bit of trouble with it.
Previous to the second failure I had an old electric motor I thought might need looking at and called a motor rebuild facility in Columbus, Ga. The guy asked me some questions and said I didn't need it rebuilt. I thought that a novel idea, guy hasn't seen it and pronounced it fine which told me I could trust him. One of the questions he asked was whether it had oil cups. I said yes. He said put Mobil 1 in it and forget it. I had used it at that time for about 200,000 miles so I asked him why he was so convinced and he said in effect they put it in the motors they rebuild and recommend it to everyone they see and they had never seen a electric motor burned up with Mobil 1 in it and they rebuilt hundreds of them that had not failed to that time. He said they had used it for about ten years in their rebuilds if I remember correctly.

Link Posted: 8/24/2006 5:30:23 AM EDT

Originally Posted By Humpy70:
Highpower target shooters only have two sighter shots at any given range and they need X ring accuracy by third shot better yet by second shot

So go to match with a dirty barrel you know that shoots? Don't clean and then hope to hit target.

Ed' Red Formula and a whole bunch more homemade stuff for shooters. This page has saved me tons of cash.
Link to "Homemade Firearm Cleaners & Lubricants"

Can you clean a bore with Mobile 1?
Link Posted: 8/24/2006 9:40:47 AM EDT

Originally Posted By AtlantaFireman:

Originally Posted By Humpy70:
Highpower target shooters only have two sighter shots at any given range and they need X ring accuracy by third shot better yet by second shot

So go to match with a dirty barrel you know that shoots? Don't clean and then hope to hit target.

Ed' Red Formula and a whole bunch more homemade stuff for shooters. This page has saved me tons of cash.
Link to "Homemade Firearm Cleaners & Lubricants"

Can you clean a bore with Mobile 1?


Go to a match with a load that works with your barrel and a cleaning regement that you know works too. Know your load and your rifle, keep records, and get on target. Know your come-ups for each shooting range (and maybe each relay), and keep track of everything.

Clean out the carbon fouling, test and see how cleaning copper fouling affects precision. John Holliger has recommended just hitting the throat with bore paste, and I can see how that would help prevent disruption of the jacket. I can also see how taking the barrel down to bare metal could be bad, as you might need some rounds to build up a 'good' level of copper foulding before the rifle will group.
Link Posted: 8/24/2006 10:15:44 AM EDT
I have three of John Holliger's SPR barrels (White Oak Armament). These are extremely accurate with Sierra 77 grain bullets: ABSOLUTELY FANTASTIC.
Link Posted: 8/24/2006 10:22:51 AM EDT
I have heard of him but that I remember never had the pleasure of meeting him. I have also heard his barrels are quite acceptable. I have a friend who shoots beer cans at 300 with his and loves it.(The beer and the shooting that is haha.)
Link Posted: 8/24/2006 11:04:33 AM EDT

Originally Posted By AtlantaFireman:
I have three of John Holliger's SPR barrels (White Oak Armament). These are extremely accurate with Sierra 77 grain bullets: ABSOLUTELY FANTASTIC.


I have excellent results with 77 SMKs and the 1:7 WOA barrel too. nothing wrong with 80s either.

My brother runs a 1:8 Rock River and it does great with 69gr SMKs. He shoots a thursday night leage and printed a master score with 69s across the course!

Anyhow, John Holliger is a very nice man and excellent shooter, very active in Illinois highpower and supports the IL Junior team (Illinois Hard Dogs.) I started smothing the throat with a small amount of bore past and this seems to work really well with chrome lined barrels too. I shot some RORG M855 that left a nasty carbon ring in the throat, and hitting it with JB made a big difference.
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